No matter the medium used, the value depends on the artist !! The medium for yours is called "pastel" !! Similar to charcoal but in a range of softer colors and frequently used for portraits because of the variations in flesh colors !! Believe me,, I have tried it and it isn`t easy to use !! The signature is the artists and the year is was done !! I would say that it has a small value if any at all !! However if you like it,, it may have more than monetary value just to hang in your home !! Many things that I have little value in dollars,, but if I like them,,they are priceless !!